My first boat is overweight because I used far too much epoxy, got crazy with filleting/taping (with heavy tape, I don't remember the gauge). Basically, I figured "this little bit won't hurt..." but didn't realize how all the little bits added up to a big, heavy bit. Oh, well.

I considered eliminating the sheer clamp altogether, as I'm stripping the deck, but decided to keep it as the NBXL's deck-to-sheer angle is almost 90 degrees. Tape would be less effective going around a turn like this... so, I'll keep the clamp.

Using 3mm epoxy after pre-coating the insides with 2 oz. glass sounds like a great idea. I just don't know where to get 3mm okume in the SF bay - McBeath's doesn't have any, and won't order it. I'll keep looking...

Great point about the shop-vac. I was actually concerned about running the motor like that, but forgot about the cooling issue... well, I'll think about it. I was going to bag just the hull, and wanted to avoid putting the whole boat in the bag. I was concerned that 1 atm of pressure over the whole boat would crush it - by using the hull itself as one side of the vacuum vessel, (basically just putting the plywood and glass in the vacuum) atmospheric pressure backs up the inside of the boat, and I eliminante such concerns.

So, how does this sound. 3mm ply, 2oz glass on the inside (applied pre-assembly per your technique) 4oz tightweave outside, further 2oz layer on bottom of hull. Stripped deck, 4oz tightweave top and bottom, bottom supported by foam/graphite ribs and stringers. Extra reinforcement around cockpit, aft-deck for re-entry.

I'll experiment with some panels and my vacuum setup - if I can see a significant difference in weight between them (equal rigidity and fail strength) then I'll do it - otherwise I won't bother.